Manifold devices and methods of delivering droplets or particles of drugs to the respiratory system, especially the lungs have been proposed. In many of these devices, the aforementioned droplets or particles are picked up due to the Venturi effect as the airstream passes over the drug supply on its way into the respiratory system. Contemporary devices suffer from several drawbacks, including the very low ratio of drug that reaches its target location (e.g. the terminal bronchioles and alveoli); and the skill and cooperation required from the patient using the device. It would be highly advantageous to provide a method of improving the delivery of the aforementioned droplets or particles to the target tissues, such as the alveolar walls of the lungs, to ensure better uptake of the drugs. Moreover, it would also be highly advantageous to prepare the lungs prior to drug dispersion for optimal drug uptake.